Does a Solar Powered Generator Work in the Winter?
Solar power is hotter than ever. With more and more people looking to get off the non-renewable electrical grid, drawing energy from the sun is becoming increasingly popular.
But for homeowners who live in areas with heavy winter storms or frequent days of little to no sunlight, one concern is: Do solar generators work in the winter?
This quick guide will answer your question, including how solar generators work in the winter and the factors affecting their efficiency. You’ll also learn tips on the best ways to optimize your energy generation so that you can have solar power even on the cloudiest, snowiest days.
Do Solar Generators Work in the Winter?
In the wintertime, the sun’s rays are weaker due to the Cloud cover, the Earth’s distance from the sun, and the tilt of the Earth’s axis.
You might think that during the summer months, the reason your location is hotter is because it’s closest to the sun. But that’s incorrect. When the Earth is farthest from the sun in July is when it’s hottest in the Northern hemisphere. It all has to do with the tilt of the Earth’s axis. When it faces the sun, that’s the season we call summer. As the Earth revolves around the sun in winter, it spins on its axis and tilts away from the great ball of light.
Unless you live somewhere the sun only comes out once or twice a month during the winter, your solar panels will still capture the sun’s energy and generate power to store in the generator.
Even in sub-zero temperatures, solar generators still catch sunlight and turn it into power. The sun’s light is always bearing down on us, even if we may not feel it. The surprising thing about solar generators is that you can get as much power from the sun on a cold and cloudy day as you can in the extreme, cloudless heat.
All that solar panels need to collect solar power is exposure to the sun. The photovoltaic cells convert this sunlight into electricity, even if it’s a small amount. Solar generators aren’t like fires that only generate heat as long as they burn. Months after PV cells have converted solar energy and stored it in the generator’s battery, you can continue to dip into the energy reserve.
It is less likely in the winter that your PV panels will have exposure to the same sunlight that you get in the summer. But even in rain and clouds, you can still absorb the sun’s energy with your solar power generator.
How to Utilize Solar Power in the Winter
The primary way you can use your solar generator in the winter is by storing electricity in a battery. The generator is essentially a giant battery with solar panels attached. It draws its energy from the sun rather than a traditional power source like a wall outlet.
Solar generators typically gather less energy during the winter than in the summer, but power outages happen more in the summer. When temperatures increase, you run a higher risk of transformers bursting and power outages that shut down entire neighborhoods. Then again, surging winter storms can snatch the power from homes and entire neighborhoods for the same reasons. In either case, you can participate in community solar to keep the lights on during summer or winter.
Community solar is a program rolled out by the US Department of Energy. Any solar project in a defined area where the energy generated flows to multiple users, households, and businesses can be part of a community solar program.
Community solar, in other words, is when multiple residences buy or lease a portion of solar panels in a local array and receive an electric bill for their share of use. The rates users pay are drastically lower than what they would pay to use electricity from non-renewable resources.
Though there are still issues to smooth out with community solar, about a third of states have now launched pilot programs.
Besides joining a community solar program in your state, you can also optimize energy efficiency in winter by purchasing a reliable solar-powered generator.
Home Backup in Any Weather—The EcoFlow DELTA Pro Solar Generator
The EcoFlow DELTA Pro with the 400W portable solar panel is the industry’s leading solar-powered generator.
With a starting capacity of 3.6kWh that you can expand to 25kWh, it’s the ideal solution for home energy backup. Say goodbye to restless nights worrying if snowstorms or downed power lines will leave you without power — the DELTA Pro keeps your home powered for hours.
It offers home integration with your household electrical circuits and can power up to 99.99% of heavy-duty devices, including televisions, refrigerators, laptops, and more.
The protective case included with the DELTA Pro also turns into an adjustable stand. You can use it to tilt your solar panels 40-90 degrees for maximum exposure.
Once fully charged, the Delta Power Station can power 13 devices simultaneously with its outlets.
For energy independence, nothing compares to the DELTA Pro.
Power in a Pinch—The EcoFlow River 2 Pro Solar Generator
This lightweight, portable machine offers 768Wh capacity — a powerhouse for running a 500-watt refrigerator for over 3 hours or an electric kettle for about 1 hour. You can wait out the power outage in style and warmth when the lights go out, with a warm cup of coffee to tide you over for the storm.
The River 2 Pro can charge from 0% to 100% within 70 minutes. It’s compatible with 80% of high-wattage home appliances with 4 800W AC outlets and comes with a portable and foldable kickstand panel. It’s the solution you want when you need power in a pinch.
Portable Solar Panels
Portable power stations alone aren’t enough to generate electricity. For that, you need solar panels to draw energy from the sun.
EcoFlow portable solar panels outpace the industry average of 15-20% for solar conversion rates. With EcoFlow, you can expect a 23% conversion rate. Even with low light conditions in the winter, you can expect more energy from the sun.
FAQs
The durability and weather resistance of solar panels has vastly improved in recent years. Inclement weather like snow will not ruin your solar power system. However, it might affect the efficiency rating.You may have to regularly remove the snow from the surface of your solar panels. Blockages on the panels can hamper sun absorption. However, the dark, reflective glass covering the surface of solar panels gets warm quickly and accelerates snow melt.The good news is that snow on the ground reflects light. Solar generators absorb the reflective power of the snow and convert it into electricity that you can use to power any of your electronic devices.
There may be a dip in power generation during the winter months, as there’s more Cloud cover and less direct sunlight. Still, there’s no reason to fret. Sunlight still strikes the surface of the Earth constantly. The National Oceanic and Atmospheric Administration estimates that 173,000 terawatts of solar energy hit the Earth simultaneously, all the time.For perspective, a regular electrical wall outlet generates 1800 watts, and a portable solar generator can produce up to 7,500 watts. That is a significant amount of energy to churn through.
You don’t need to clean light dustings of snow on your solar panels. The heat generated by the panels will melt the snow. The thermal cycle generates a significant amount of energy, so the surface of these panels can be hot to the touch, even in the coldest weather. Plus, where there’s snow, there’s usually wind, which will blow snow straight off the slick surface of the panels. The only problem that you may run into is heavy snowfall. With more weight added to the panel’s support structure, there is a higher chance of structural damage. Portable generators like the EcoFlow River 2 and DELTA series are solidly built. Plus, with the tiltable stand, you can angle the panels so that snow doesn’t have a chance to pile up. These generators will help you power through a storm.
Power Any Time
Winter doesn’t have to mean energy insecurity — with solar-powered generators from EcoFlow, you can optimize your solar energy generation even in winter conditions. Visit our online store for solutions to all your power needs, no matter the weather.
EcoFlow is a portable power and renewable energy solutions company. Since its founding in 2017, EcoFlow has provided peace-of-mind power to customers in over 85 markets through its DELTA and RIVER product lines of portable power stations and eco-friendly accessories.
Can a Solar Generator Power a House? [Expert Answer]
Solar generators are enormously helpful and versatile devices. They harness the sun’s power and convert it directly into energy for you to use throughout your home. They are a convenient way to keep your much-needed devices and appliances going throughout power outages or similar emergency circumstances.
That sounds incredibly impressive, but are they actually up to the task of powering an entire home?
That’s what we’re here to answer.
This guide has the experts weigh in on whether a solar generator can keep your house running during an outage and factors to consider. We’ll also take you through the process of connecting your solar generator to your electrical panel. By the end, you’ll be the expert.
Can a Solar Generator Power a Whole House?
The short answer is yes, they can, but there are many variables to discuss. Not all solar generators are capable of producing enough energy for whole-home systems. Instead, you have to consider the device you want to use as a home backup system and how you want to use it during a power outage.
You first need to establish how much energy your house consumes on average. You need to know this before purchasing a solar generator to ensure they pack enough power to keep your home running when you need it. If you buy a solar generator that doesn’t produce enough energy, it may become a wasted investment and could even put you in danger in an emergency.
You should also consider how much energy your solar generator needs to supply. If you suffer from frequent power outages, you may want to invest in a powerful generator to keep everything in your home running when you’re disconnected.
A whole-home system has a substantial energy demand but isn’t unachievable. On the other hand, if you don’t suffer from power outages very often, you might just want a generator that can keep your necessities going for a few hours. That will drastically change the requirements of your solar generator.
Instead of thinking about how much energy your home produces as a whole, consider what you will need most in an emergency. When choosing your first solar generator, a detailed emergency plan will give you greater clarity and specificity. You might not require something that can power your entire home. Sometimes, you only need a device to keep the necessities going.
What Size Solar Generator Do You Need to Power Your House?
An easy rule of thumb to follow is that the larger the solar generator, the more power it will be able to produce. Most power generators rate their power capacity via wattage. The higher the wattage, the more they can power at any time. Before making an informed purchase, you need to know how much wattage your essential appliances require.
Besides the capacity, you want to look at a product’s peak power and continuous power. Peak power is how much a generator can produce when it first starts up. Continuous power is how much a generator can keep going for an extended period.
When purchasing your first generator, you need to pay attention to both so that your system can generate enough power to run a device or appliance and keep it running.
How Do You Connect a Solar Generator to Your House?
Once you’ve found the perfect solar generator, you need to be able to connect it to your home. Luckily, this process isn’t too complicated.
The best and safest way to achieve this is by using a transfer switch. Several varieties are available, and although they function differently, they all complete the same goal. They are a go-between for your solar generator and home electrical panel circuits.
In addition to connecting your solar generator to your house, transfer switches make power utilization much more manageable. You are in total control, as you can shut off any unneeded power circuit to further maintain your energy supply. It can prove especially helpful in emergencies, where you will want to prioritize food and light sources.
There are three types of transfer switches currently available for this purpose. To give you a better understanding of each, we’ve broken down everything you need to know.
Automatic Transfer Switch
As their name suggests, automatic transfer switches will automatically detect power outages and use the stored solar power to get you up and running again as soon as possible. This intuitive design makes it highly popular among those who need high reliability from their electrics.
These transfer switches will also turn themselves off once they detect that the power grid is up and running again. They require minimal intervention, so there’s a lot to love. The only potential downside is the price, which can be significantly higher than other options.
Manual Transfer Sub-Panel Switch
If you are looking for something like an automatic transfer switch that doesn’t carry the hefty price tag, a manual sub-panel switch could be the answer. As you probably expect, the drawback is that you must utilize it manually. You don’t have the benefit of automation.
Whether this is a deal-breaker for you or not is entirely personal and largely relies on your individual needs. Manual activation might not be as effortless as automatic, but it might be all you need if you only experience occasional power outages.

Breaker Interlock Connector
Last on our list is one of the most popular options. Breaker interlock connectors are often the most affordable while still championing flexibility.
You have a choice over which home appliances or gadgets you wish to power with your solar generator, alongside a built-in amp meter to prevent overloading. They are easy to use and do the job well, so their popularity is understandable.
How Do You Use a Solar Generator at Home?
You don’t need to do anything too extreme to use your solar generator effectively. That’s part of the attraction. It won’t require much upkeep as long as you keep the device in the sun sufficiently to recharge and connect it properly via the appropriate transfer switch.

The two key areas you need to pay attention to are how to recharge them effectively and maintain them without causing any damage. Follow the steps below:
How to Recharge Your Solar Generator
One of the greatest attractions of a solar generator is that all you need to recharge them is the power of the sun. Given that we have access to the sun every day, this is a significant bonus! Just make sure to position your generator correctly to make the most of the sun’s power. Many solar generators will feature panels to absorb the sun’s energy, so make sure to place the device in a way that exposes it to as much sun as possible.
To maximize how much energy you can receive from your solar generator, you should aim to keep the panels in the sun for anywhere between six and eight hours daily. Some generators have specific input rates that you need to heed. Otherwise, you could end up damaging them.
Additionally, some generators have a dual-charging feature, which is enormously helpful. It means you can charge both via your wall (or even car battery) outlet and the sun. Dual-charging capability vastly increases charging speeds, making your solar generator even more efficient.
How to Maintain Your Solar Generator
In addition to charging your solar generator properly, you also need to know how to maintain it. If you don’t keep it in the right conditions, you could damage it before you even get any meaningful use out of it. Listed below are some of our critical criteria to keep your generator as healthy as possible.

- Charge: You should always aim to keep your generator between 50-70% of its full charge. Additionally, we recommend fully discharging and recharging your generator every six months to keep it in optimal health.
- Cleanliness: Despite providing clean energy, the generator may still get dirty. In most cases, you should only ever need to use a non-abrasive cloth to clean your generator. Don’t use water or harsh chemicals, as this may damage it.
- Ventilation: Even solar generators get hot sometimes, so make sure you place the device in a well-ventilated location. Though it may harness the sun’s power, it will last longer if you avoid overheating it.
- Environment: Though you should keep your solar generator (or its panels) outside so it can absorb the most energy, ideally, it should only be exposed to sunlight. Rain and wet environments may cause damage or shorten the generator’s lifespan. After all, it’s still an electrical product.
- Safety: You should also keep the generator away from flammable or combustible materials. Solar generators can produce a surprising amount of energy; though they are safe, it’s always better to minimize risk as much as possible.
Conclusion
That just about covers it! Everything you need to know about solar generators and their capability to power your home. The truth is, solar generators are a highly versatile and convenient way to keep your house running when you need it most, as long as you pay attention to the critical criteria we’ve listed. If you’re looking for a powerful solar generator to keep your home running in an outage, consider the EcoFlow Delta series. These robust generators use clean energy and exceptional recharge rates. Shop today to outfit your home.
EcoFlow is a portable power and renewable energy solutions company. Since its founding in 2017, EcoFlow has provided peace-of-mind power to customers in over 85 markets through its DELTA and RIVER product lines of portable power stations and eco-friendly accessories.
CleanTechnica Tested: The EcoFlow DELTA 2 Max Solar Generator
EcoFlow seems to be on ‘a can’t stop, won’t stop’ mission to transform not only the world of portable solar generators, but is also starting to develop a host of appliances that take advantage of these portable power sources.
Following on the heels of a successful lineup of portable power stations and solar panels, EcoFlow has introduced the DELTA 2 Max portable power station. This two kilowatt-hour unit packs a punch with its ability to push out nearly 2,800 watts of continuous AC power output.
We pushed this thing harder than we had pushed any portable power station we’ve tested, and it simply refused to die. With 2,800 watts of AC power output capability, it can easily power just about any appliance in the house, including power tools, 110 volt welders, and EV car chargers, in addition to the usual assortment of refrigerators, cameras, drones, and the like.
Charging The EcoFlow DELTA 2 Max
The EcoFlow DELTA 2 Max is well equipped to pull power in and push it back out again. When plugged into an AC wall outlet, it can absolutely gobble the power down. It features a choice between slow charging at around 400 watts, or fast charging at up to 1,800 watts. Recharging in fast mode translates to about an hour and a half for a full charge, with the charging speed tapering off as the battery pack fills up.
When pulling down 1,800 watts of power at a time, the cables to the wall start warming up, and it’s especially important to be sure you’re using the cable supplied by EcoFlow, as the cables made by mere mortals won’t likely hold up to this amount of power draw for very long.
EcoFlow has also continued to build out its array of solar panel options, and sent along its 220 watt bifacial folding flexible solar panel for us to test. This is the first portable folding bifacial panel we’ve seen, and sandwiches the bifacial solar cells between two layers of clear durable plastic.
Bifacial solar panels still produce the majority of their electricity from sun hitting the top of the panel. This means the panel itself is directional, and as such, it is important to ensure that the side labeled as “sun facing” should be oriented appropriately. This is the side with the wires coming out of it, which is a bit confusing, but the cables have plenty of length to make it work with minimal fuss.
The back side of the panels harness light reflecting up from the back of the unit. This is helped along by the stand for the panels, which doubles as the padded case for the unit. The inside of the stand is a bright white surface, which helps reflect some of the light passing through the panels and from nearby areas back up to the rear of the solar panel. In our testing we did see production over 200 watts, although it was difficult to achieve on the grassy surface we tested it on. It performed slightly better on lighter colored cement, which is in line with EcoFlow’s estimates in the image above.
Discharging
We spent an entire day using this as the power source for our heat gun as we vinyl-wrapped a car, running the heat gun, music, and our devices off of it. The realization that these portable power stations can not only be used when the power goes out, but also as portable power sources in the home for situations where an extension cord would normally be needed was eye-opening. It almost felt like it was bopping along with the music as we worked. Granted, our heat gun only pulled between 500 and 900 watts, depending on the temperature and throughput volume, but that was just the start.
We ran it through the normal gamut of kitchen appliance tests, ranging from our 800 watt kettle up to the full complement of 1,500 watts worth of blenders, mixers, and kettles, and again it hardly noticed. The EcoFlow DELTA 2 Max boasts 6 AC outlets on the rear of the unit, as well as two 12 volt, 3 amp barrel connectors, and a standard 12 volt automotive outlet. On the front of the unit, four USB-A outlets and two USB-C outlets make it easy to charge all your devices without the need for an extra AC adapter.
We ran a small automotive refrigerator unit from the 12 volt barrel outlet, and pulling between 5 and 55 watts depending on whether the compressor was running or not, the EcoFlow DELTA 2 Max kept up without missing a beat. This is a minor task in terms of output, but mirrors real world scenarios customers will likely use it for.
It’s easy to imagine this unit being put to task as a backup power station for a home. Granted, with just two kilowatt-hours of storage capacity, you’ll need to tightly manage how much power you’re pulling. With 2,400 watts of continuous output and a staggering 4,800 watts of peak power output, this unit would have no issue supporting a compact tiny house or RV setup by itself. Adding in a solar panel or two further extends that capability.
Overall
The EcoFlow DELTA 2 Max is an extremely capable portable power station, though it is a bit on the heavy side at 50 pounds. That calls into question the portable nature of the unit, though. With something of this size, it’s likely you’re not going to be moving it around a whole lot. That holds true for most large battery systems, as their weight and the relatively fragile nature of the battery cells themselves makes it a good idea to leave them stationery as much as possible.
The EcoFlow DELTA 2 Max is 1,899, which is a slightly higher price than most of the competition in the portable power station space. EcoFlow currently has the DELTA 2 Max on sale and is currently including two 110 watt solar panels free with purchase. That definitely helps the value proposition, but it’s still a premium unit and is priced as such.
For more information about the EcoFlow DELTA 2 Max and the 220 watt bi-facial folding solar panel, head over to EcoFlow’s website.
EcoFlow DELTA 2 Max Specs
- Weight: 23 kg
- Capacity: 2,048 Wh
- Battery Chemistry: LFP (LiFePO4 battery)
- Cycle Life: 3,000 cycles to 80% capacity
- Dimensions: 497 × 242 × 305 mm /19.6 × 9.5 × 12 in
Input
- AC Input: Fast Charge 1,800W, 15A
- DC Automotive Input: 12V/24V battery, 8A
- DC Solar Input: 11-60V 15A, single port 500W; dual port 1,000W
Output
- AC Output: 2,400W continuous, 4,800W peak
- AC Outlets: 6
- DC 5521 Outlets: 2 ports, 12.6V, 3A, 38W Max per port
- USB-A Outlets: 2
- USB-C Outlets: 2
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History of Solar Generators the EcoFlow Delta Pro
Technology has come a long way in recent years, and the push for clean energy is driving innovation like never before. 79% of Americans want to transition to entirely renewable energy, and one of the easiest ways to do that is by tossing out your old generator.
Well, solar generators, also known as portable power stations, have come a long way in recent years, overcoming odds and substantial obstacles. Let’s talk about the fascinating history of the EcoFlow Delta Pro and other solar generators on the market.
How Solar Generators Came to Be
Solar generators were made popular by a 2012 startup known as Jackery, which still sells popular solar generators today. These were supposed to be portable power stations designed for camping trips. Today, some solar generators can be used on job sites, in RVs, or even for home backup.
Of course, it wasn’t just portable power stations. Some systems were designed to use solar panels on your rooftop for backup home power, like the Tesla Powerwall and other similar models that started making sales in April of 2015.
For portable power, Jackery was the first to create a large battery that you could charge in the car that could also use solar energy. Since then, several other companies have joined the mix, and they’ve come a long way. However, the best year for advancements was 2021, which we will talk about soon!
Challenges in the Market
Without a doubt, the biggest challenge in the solar generator market is competing with gas generators for output, lifespan, and price. Newer technologies are harder to optimize for low prices, so this is unsurprising. However, one company may have finally found the formula. Let’s talk about that!
EcoFlow Delta Pro History
Without a close second, the EcoFlow Delta Pro is the best solar generator on the market. You can read our full review of the Delta Pro for more information, but we can assure you that no other system lives up to its standards, and it has a fascinating history to back it up.
History of EcoFlow
Believe it or not, EcoFlow was established as recently as 2017 by a battery engineer named Lei Wang in China. Wang had previously worked for DJI making drones and launched his own projects using crowdfunding platforms like Kickstarter and Indiegogo. Since then, it’s become a serious topic of discussion in the world of tech!
Delta Pro Kickstarter
Other than its state-of-the-art features, the most impressive achievement of the Delta Pro was breaking Kickstarter’s all-time record for the most-funded project. Launched on July 15, 2021, the two-month campaign took off to raise over 12 million from 3,199 supporters, breaking the previous record by over 4 million. Not only that, but they raised their first 1 million within 10 minutes of launching the campaign.
The campaign received so many positive reactions from tech junkies, investors, and clean energy lovers due to EcoFlow’s promise of making a clean and portable power station that’s equipped for home backup. Well, they delivered!
Sales
Since its launch in 2021, the Delta Pro has become one of the most sought-after portable power stations on the market, but they’ve had one challenge. Their price tag has set them back on sales, but let’s do the math.
If you spend 3,500 on a Delta Pro that lasts for daily use, that breaks down to less than 1 a day of heavy use. Keep in mind that the free energy you’ll receive from its advanced solar panels is worth more than 1 a day, but we’ll ignore that for now. Let’s compare that to another popular model.
If you buy a Jackery 1000 for 1,099 and it’s only geared for 600 lifecycles, that works out to 1.83 per day with a lot less energy output for each lifecycle. Yes, the Delta Pro costs more upfront, but there are payment plans that allow you to purchase the system for 100 a month, making it affordable to nearly anybody who wants it!
See for Yourself
Now that you know the history of the EcoFlow Delta Pro, you can see why it’s so popular. A lot of thought, time, and persistence went into crafting this device for consumers, and it truly is the only solar generator of its kind. Stay up to date with our latest information on your favorite products and feel free to shop with us for free shipping and a price match guarantee!
Review: The EF ECOFLOW Delta Max Solar Panel Bundle is Portable, Powerful, and Sustainable
Solar is one of the most well-known renewable energy sources, but harnessing it for personal use has been difficult, especially if you’re unable to install permanent panels on the top of your home. The EF ECOFLOW Solar Generator Delta Max and Solar Panel Bundle aim to change that, and it succeeds if your needs fall within its power output limitations.
Before we get into the tech specs, it’s important to report that this bundle costs 2,199 at the time this review is being published. That’s a big investment to make, especially when you consider the fact that four rooftop solar panels can cost up to 400 less. The difference is that EF ECOFLOW’s bundle includes an ultra-high-capacity battery to store the energy absorbed by the solar panel. The energy can be used immediately or saved for emergency situations or multi-day camping trips. This bundle may elicit some immediate sticker shock, but EF ECOFLOW has actually knocked 550 off its original price tag due a price reduction and free coupon provided when you shop on Amazon.
What is the EF ECOFLOW Delta Max Solar Generator Bundle?
Specs:
EF ECOFLOW Delta Max — Size: 19.6 H X 9.5 L 12 W Inches — Weight: 47.9 pounds — Capacity: 2,016 WH (watt hours) — Ports: Two USB-C, four USB-C, 2 DC, one car output, six AC outputs — Maximum Power Output: 2400W (watts)
EF ECOFLOW 220W Solar Panel — Size: 32.3 L x 72 W x 1 inches — Weight: 20.9 pounds — Maximum Power Output: 220W — Number of Panels: Four
My interest in solar energy has led me to trying out low-powered panels from companies like Grouphug and Anker. which are designed to charge portable electronics like a smartphone, tablets, or handheld game consoles. While impressive for their size, these solar panels lack the power output necessary to charge or run larger gadgets, be they laptops or small appliances. EF ECOFLOW’s 220W solar pane l can absorb and convert far more energy from the sun, and the Delta Max allows you to easily use it to power much more demanding gadgets. These are the most powerful sustainability tools I’ve tested in my career, and they’ve recalibrated my expectations for solar-powered technology in the future.
Setup
If you’ve never used a solar panel before, you’ll be happy to learn that EF ECOFLOW has made the setup process pretty painless. Using its instructions, I was able to set up the 220W Solar Panel and connect it to the Delta Max in about 20 minutes. It’s important to recognize that I did need the help of a friend to set up the solar panel because it’s several feet long when it’s fully unfolded. This makes it unwieldy to move around as one person. You may be able to assemble it on your own if you lean the panel against the side of a house, or other tall, sturdy surface.
Setting up EF ECOFLOW’s solar panel had three basic steps: removing it from the included carrying case, unfolding it to reveal its four-panel array, and attaching the panel to its opened carrying case using a set of included clips and straps. That last step is what required me to seek a friend’s help. The opened case acts as a stand for the solar panel, and angles it upward to absorb the sun’s rays more effectively. Attaching the two pieces to one another is pretty simple because the solar panel has holes on its top and bottom edges, so you’ll know the exact places to hook the case onto. I shouldn’t have been surprised that EF ECOFLOW’s solar panel case could be used for more than just protection and easy transportation, but I was.
With the solar panel set up, it was time to connect it to the Delta Max Solar Generator. This gadget looked imposing, and weighed a ton, but was incredibly easy to use. All I had to do was connect the solar panel’s power cable to a port on the Delta Max. The solar generator instantly recognized the solar panel and began charging. The Delta Max’s screen showed its current charging rate (measured in watts), along with how many hours it would take to fully recharge the battery inside. This was extremely helpful because it let me know whether I had to move the solar panel around, or adjust its angle. It’s common sense that a solar panel will be more effective when you move it away from shade cast by a tree or the side of a house; knowing that a half turn to the left can increase the panel’s effectiveness by 15 percent is much less intuitive.
First Impressions of the EF ECOFLOW Delta Max
I tested the solar panel’s efficiency in a couple of spots on the front lawn of a suburban home on a sunny day, and saw firsthand how much moving it around can make. In a slightly shaded area, EF ECOFLOW’s solar panel was only transferring energy to the Delta Max at a rate of between 10 and 20 watts. It would have taken dozens of hours to charge it up at that rate. By moving it into a sunny spot, the solar panel was charging the Delta Max at a rate of 140 watts, and would recharge the solar generator in 11 hours. Yes, that’s still a long time, but the difference was remarkable. It should be said that you can charge the Delta Max by plugging it into an outlet — which admittedly takes less time because there’s no variability in how much energy it’s absorbing — so you’re not out of luck if weather is crummy.
The bundle I was sent for review had a single solar panel. but you can hook two of them up to the Delta Max at one time. Under optimal conditions, you can charge the Delta Max at a rate of up to 440 watts. Based on my experience, that’d mean being able to fully recharge the Delta Max in just between five to six hours. Each solar panel costs 549, though, which makes its very expensive proposition. We hope that improvements in manufacturing processes lead to price cuts on solar panels over the next few years regardless of the manufacturer. EF ECOFLOW says you can use any solar panels that use the same EcoFlow Solar Connectors, aka plugs that can connect to the ports found on the Delta Max.
Space and Charging Considerations
A persistent problem you may have when using a solar panel to charge the Delta Max is finding enough space to set it up. The solar panel requires several feet of clearance when it’s unfolded, which makes it a no-go in crowded areas, including densely populated public campgrounds. If you have the luxury of a front or backyard that gets good sun coverage, or take trips to a private campground there’s no doubt that EF ECOFLOW’s bundle of a solar panel and the Delta Max can help you use renewable energy more easily, but space is an absolute necessity. It’s worth noting that the EF ECOFLOW’s solar panel is pretty compact when it’s folded up. This is helpful for both at-home storage and for times when you want to pack the solar panel up in your car. The solar panel’s protective case has a handle, which makes it easy to carry around, too.

At first glance, EF ECOFLOW’s Delta Max may look like the more boring part of the company’s sustainability tech bundle because it can be written off as a huge battery pack. That’s true to some extent, but the Delta Max is so well constructed and thoughtfully designed that it’s worth recommending on its own. The 48-pound solar generator has a capacity of 2016 WH (watt Hours) and can output up to 2,400 watts of electricity at a time. EF ECOFLOW says the Delta Max can be fully recharged in about 65 minutes when connected to an outlet using the included AC adapter, though I stuck to solar charging during my tests.
The Delta Max’s high battery capacity and generous number of outputs makes it a natural choice for campers, or anyone who wants to be prepared to power their essential electronics in the event of a blackout. The frontside of the Delta Max features two 100-watt USB-C PD (Power Delivery) ports and four USB-A ports, two of which support fast charging speeds. These ports are perfect for charging smartphones, tablets, game consoles, headphones, Bluetooth speakers, and all manner of other portable electronic devices. I connected a handful of gadgets from these categories to the Delta Max at once and all of them started charging immediately.
The Delta Max’s front side also houses its LED color display, which shows how much power it’s outputting in real time, and how many hours it can run before running out of juice. This is extremely helpful information because it’ll help you moderate your energy use to avoid dealing with a dead battery. The Delta Max’s screen also includes the traditional battery percentage number, which ticks down as you use it. You can check the solar generator’s energy levels by staring at the screen, but you also have the option to monitor that information on the go using the EcoFlow mobile app. The app is entirely optional, and is not required to use the Delta Max. That said, it was helpful to keep tabs on its battery levels when I wasn’t in the same room.
Using this feature requires you to create an EcoFlow account, and keep the Delta Max in an area where it can maintain a strong connection to an active Wi-Fi connection. The app walks you through the process of how to connect the power generator to your phone, and eventually the internet, and is pretty user-friendly. Overall, I’m happy that the app exists, but glad it’s not a requirement.
On the back of the Delta Max, you’ll find six AC outlets, a car power outlet, and two DC outlets. The car power outlet was of particular interest to me because one of the gadgets I rely on regularly is a tire inflator that’s powered using that connector. Sure enough, the inflator sprang to life when I plugged it in and hit its power button. I’ll always keep the tire inflator in my car, but it’s good to know that I can rely on the Delta Max if I decide to inflate bike tires indoors. While the solar generator’s car power outlet served one of my niche needs, its AC plugs are the real stars of the show. These ports allow you to use the Delta Max to power appliances like coffee makers, microwaves, and toasters, or high-powered electronics like big-screen TVs and party speakers.
Battery Power
My big battery test was using the Delta Max to charge an electric bicycle. In one hour, the solar generator charged the bike’s battery by approximately 30 percent (its screen doesn’t show battery percentages) while draining the Delta Max by only 7 percent. During that test, the Delta Max displayed that it was outputting power at a rate of approximately 120 watts, and could sustain that level of energy output for 14 hours. That means I could fully recharge the bike several times before having to top up the Delta Max. Since I used solar energy to charge it, my entire e-bike charging system used 100 percent renewable energy. It may seem a little idealistic considering the price and space requirements of EF ECOFLOW’s bundle. but it was the highlight of my testing time with these gadgets.
EF ECOFLOW says the Delta Max should last 800 recharge cycles, which may seem alarmingly low at first, but makes sense if you take a step back. This isn’t an inexpensive battery pack you’ll drain and recharge after a day of casual use, it’s designed for extreme conditions like camping or multi-day blackouts. You may only recharge the Delta Max once per month, in which case the solar generator would last 66 years without needing to be replaced. If you charged it once a week, the Delta Max could continue to hold a charge for 15 years. You may also be worried about the Delta Max slowly losing its charge while sitting on a shelf between charges, but I didn’t find that to be the case. The solar generator kept the exact level of charge after two weeks of not being used. You should check the Delta Max once every couple of months to make sure it hasn’t lost a charge, but I wouldn’t worry too much about it.
Final Thoughts on the EF ECOFLOW Delta Max
Three final observations about the Delta Max that stood out to me. First, its weight didn’t turn out to be much of an issue because of the handles on either side of its top piece, which made it easy to move around. The solar generator still weighs close to 50 pounds, but the handles helped a lot. Second, you need to press a button on the front and back of the Delta Max to turn on its two sets of ports. This prevents the solar generator from supplying energy to both sets of ports when only one set is required, saving power. Third, the Delta Max’s screen will show the ports that are currently being used by displaying a small picture of it beneath the battery indicator. The utility of these three design details didn’t occur to me at the time, but stuck out upon reflection.
The price of EF ECOFLOW’s bundle is pretty steep, but fully worthwhile when you consider how well both its solar panel and solar generator perform. The fact that the Delta Max has the flexibility to be charged independently of the solar panel. or with multiple panels connected, makes it an especially compelling tool to use during parking lot tailgates, beach parties, and other gatherings. The age of consumer-level solar charging equipment has begun, and if the gear I’ve tested from EF ECOFLOW is any indication, it couldn’t come quickly enough.
This post was created by a non-news editorial team at Recurrent Media, Futurism’s owner. Futurism may receive a portion of sales on products linked within this post.